Effect of Relaxin on Fertility Parameters of Frozen–Thawed Buffalo (Bubalus bubalis) Sperm

Abstract

The aim of this work was to evaluate the effect of relaxin on fertility parameters of buffalo frozen/thawed sperm. Sperm were incubated in the absence of capacitating agents (negative control), with a known capacitating agent such as heparin (positive control) and with 50 and 100 ng/ml relaxin for 2 and 4 h. Sperm viability, motility, capacitation and the effect of relaxin on the fertilizing ability after heterologous IVF were evaluated. Although viability was not affected, relaxin increased (p < 0.05) sperm motility compared to the negative and positive controls both after 2 h (60.0 ± 2.0, 60.0 ± 3.1, 68.3 ± 1.7 and 69.4 ± 2.7, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) and 4 h (55.0 ± 2.5, 53.3 ± 3.0, 62.2 ± 3.0 and 65.0 ± 3.2, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin) incubation. When sperm were incubated with both 100 ng/ml relaxin and heparin, a decrease (p < 0.01) of pattern A, that is low capacitation level, was observed compared to the negative control both after 2 h (54.4, 34.3 and 36.4%, respectively, in negative control, positive control and 100 ng/ml relaxin) and 4 h (51.9, 35.0 and 34.3%, respectively, in negative control, positive control and 100 ng/ml relaxin). Moreover, an increase (p < 0.01) of pattern EA, that is high capacitation level, was recorded with 100 ng/ml relaxin and heparin compared to the negative control both after 2 h (44.1, 59.3 and 57.7%, respectively, in negative control, positive control and 100 ng/ml relaxin) and after 4 h (43.0, 54.4 and 56.0%, respectively, in negative control, positive control and 100 ng/ml relaxin). Finally, relaxin increased (p < 0.01) cleavage rate compared to the negative control (57.1 ± 4.4, 72.5 ± 6.0, 71.4 ± 5.5 and 73.6 ± 2.9, respectively, in negative control, positive control, 50 and 100 ng/ml relaxin). In conclusion, relaxin has a beneficial effect on motility, capacitation and fertilizing ability of frozen-thawed buffalo sperm.

Effect of epidermal growth factor on buffalo frozen spermatozoa biometry and metabolic activity

“…Efforts to improve the preservation of bull semen are focused on the modification of extenders [1], as well as on the implementation of various bio-active ingredients to maintain the activity and fertilizing capacity, and preserve the spermatozoa membrane integrity [2].…”

Effect of relaxin on semen quality variables of cryopreserved stallion semen

“…Our result are in agreement with other studies performed in different species. In detail, relaxin has been found to improve sperm motility of boar (Feugang et al, 2015;Miah et al, 2006;Kohsaka et al, 2001), bovine (Miah et al, 2007) and buffalo (Elkhawagah et al, 2015) spermatozoa. The influence of relaxin on sperm motility and fertility has been suggested to occur through specific cell-surface receptors on sperm head and tail (Kohsaka et al, 2003;Feugang et al, 2015).…”

“…In different species, relaxin has been demonstrated to improve sperm motility (Ferlin et al, 2012, Miah et al, 2007, Miah et al, 2008Feugang et al, 2015), capacitation and acrosome reaction (Miah et al, 2008;Miah et al, 2011), and fertilizing ability of spermatozoa (Han et al, 2006;Elkhawagah et al, 2015). However, in previous studies, the effects of relaxin have been investigated on fresh semen (Han et al, 2006) or on cryopreserved semen with this compound added during thawing procedures (reviewed by Miah et al, 2015).…”

“…In addition, relaxin has been found to induce capacitation and acrosome reaction in fresh and frozen-thawed porcine (Miah et al, 2008) and bovine semen (Miah et al, 2011). Furthermore, relaxin improved the fertilizing ability of porcine (Han et al, 2006) and buffalo spermatozoa (Elkhawagah et al, 2013;Elkhawagah et al, 2015). However, to the best of our knowledge, no studies have been published to date on the effects of relaxin on quality parameters of equine spermatozoa.…”

“…However, to the best of our knowledge, no studies have been published to date on the effects of relaxin on quality parameters of equine spermatozoa. In previous studies, conducted in other species, the effect of relaxin supplementation in the sperm-thawing media has been investigated at the end of the cryopreservation process (Miah et al, 2008;Miah et al, 2011;Elkhawagah et al, 2013;Elkhawagah et al, 2015). In the present study, a different methodological approach was used, indeed different concentrations of relaxin were added before sperm cryopreservation procedures and different fertility parameters were investigated.…”